来自拟青霉属真菌的壳聚糖酶的分离纯化、理化性质及降解产物的分析(英文)  

Isolation,characterization and degradation products of a chitosanase from Paecilomyces sp.CS-Z

作　　者：史凤玉[1] 蔡爱军[1] 田辉[1] 吴楠[1] 朱英波[1,2] 

机构地区：[1]河北科技师范学院生命科技学院,河北秦皇岛066600 [2]中国科学院微生物研究所真菌学国家重点实验室,北京100101

出　　处：《菌物学报》2013年第4期721-728,共8页Mycosystema

基　　金：Supported by Educational Commission of Hebei Province, China (No. 2007449)

摘　　要：从来自拟青霉属真菌Paecilomyces sp.CS-Z的发酵液中获得一种壳聚糖酶,该酶被纯化了9.4倍,产率为48.2%。经SDS-PAGE分析确定为单一条带,分子量为29kDa,其最适pH为6.0–6.5,最适温度为55℃,在80℃处理60min后,能保持较好的热稳定性,Hg2+完全抑制了酶活,对脱乙酰度85%–95%的壳聚糖具有较高的水解活性,而对几丁质和羧甲基纤维素无活性。薄层层析和质谱分析表明该酶是一种内切酶,其水解产物为聚合度大于6的壳寡糖,其理化性质与至今报道的壳聚糖酶有所不同,为壳聚糖酶的开发提供了重要的实验依据。An extracellular chitosanase produced by Paecilomyces sp. CS-Z was purified by 9.4-fold with a yield of 48.2%. The molecular mass of the purified chitosanase was estimated to be 29kDa, as determined by SDS-PAGE. The highest chitosanase activity was at pH 6.0--6.5 and 55 ℃. The enzyme was heat-stable and exhibited the half-life of the activity when incubated at 80℃ for 60rain. Hg2＋ ions completely inhibited the activity of the enzyme. The enzyme showed high activity for hydrolysis of 85%-95% deacetylated chitosan, but colloidal chitin and carboxymethyl cellulose were not hydrolyzed. The analysis of chitosan hydrolysis by thin-layer chromatography and MS with electrospray ionization revealed the purified enzyme should be endo-type chitosanase, and a mixtures of oligosaccharides with high degrees of polymerization （DP〉6） could be produced from chitosan by enzymatic degradation using this chitosanase. Its biochemical characteristics were different from what has been reported in literature. This provided an important basis for the exploitation ofa chitosanase.

关 键 词：壳聚糖酶 壳寡糖 壳聚糖 热稳定性 拟青霉属真菌 

分 类 号：Q814.1[生物学—生物工程]